How The Digestive System Works
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What is The Digestive System?
You can think of your digestive system as a long tube that runs through you – that’s your gastrointestinal tract, or GI tract. It’s also made up of other organs; your liver, pancreas and gallbladder, and the mouth, esophagus, stomach, small intestine, large intestine, and anus. All parts of the digestive system work together to break down your food into nutrients your body needs, and allow you to pass waste.
The digestive system is important because it breaks down proteins, fats, carbohydrates, vitamins, minerals and water into nutrients small enough for the body to use for energy, growth and cell repair.
How The Digestive System Works
The GI tract starts at the mouth, continues through the esophagus to the stomach, moves to your small and large intestine and ends at the anus. While all of us are familiar with the first and last parts of the GI tract, some of the organs in the middle are bit more mysterious.
Your small intestine is divided into three parts, the duodenum, the jenunum and the ileum, in order from north to south. The small intestine mixes your food with digestive juices from the pancreas, liver and intestine, helping to break it down and push it toward the large intestine.
The large intestine begins with what’s called the cecum, then the colon and finally the rectum. Attached to the cecum is the appendix, a finger-like pocket which may play a role in immune health but is more well known for causing trouble when it gets inflamed. The main job of the large intestine is to transform the waste (undigested parts of food and fluid) from liquid into stool, which is then passed along to the rectum.
Along the way, your liver, gallbladder and pancreas also play important part of your digestive system. Your liver is a bit of a wonder organ, considering how many different things it’s responsible for. It helps make blood proteins and bile, which is a fluid your body needs to digest properly, and it removes dangerous substances from your blood, among other functions.
Your gallbladder is where your bile gets stored and concentrated so your small intestine can make use of it. And your pancreas is where insulin is made – that’s essential for controlling the amount of sugar in your blood – along with enzymes that help you get energy from the food you eat.
What other parts of the body help the digestive process?
In addition to all these organs, bacteria in your GI tract – also known as your microbiome, your gut microbiota or your gut flora – are critical for proper digestion. It’s why you hear so much advertising for products that are probiotic or prebiotic – they claim that they support a healthy environment for beneficial bacteria to flourish, though these claims often come with less scientific support than they make it seem.
Finally, it’s worth remembering that your digestive system doesn’t work all by itself. All of your biological systems are interconnected, and everything from your nerves and hormones to your blood and musculature have a part to play in your digestive process.
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